1. Field
This disclosure relates to network availability analysis, more particularly to tools for automated network availability analysis.
2. Background
Network availability has become a critical success factor for many applications, including telecommunications, video conferencing, telephony, voice over data networks applications and on-line transaction processing, among many others. The factor affecting network availability must be analyzed during design of network products and networks to allow prediction of availability properties. Designers can use these predicted properties to refine design decisions. It also provides customers with expected product qualities and trade-off choices between cost and reliability.
Current tools exist for facilitating the availability analysis, which include spreadsheet-based solutions, such as Cisco""s SHARC tool (System Hardware Availability and Reliability Calculation). Software tools include ItemSoft""s Item ToolKit(trademark) for reliability block diagrams, ReliabSoft""s BlockSim for simulation, Bellcore program for Markhov modeling, and University of Virginia""s fault tree-based analysis tool. Bellcore is a shorthand reference to Bell Communication Research. However, none of the current tools provide automated analysis.
These tools have several limitations. First, they have no linkage to the actual network topologies or products to be analyzed, and their reliability data sources. Second, they cannot automatically traverse and analyze arbitrary network topologies. Third, they do not provide automatic analysis of networks based upon failure properties.
One aspect of the disclosure is an automated network availability system. The user specifies a network topology that is received by a network availability analysis system. The network analysis system produces an availability graph using the specified network topology and performs an analysis on that graph to set forth the availability properties of the specified network topology. The system may also perform an availability versus cost analysis.